A processing brush disclosed in Patent Literature 1 mentioned below has a structure in which a rotating shaft is coaxially provided on one side surface in an axial direction of a base unit which is formed in a disk shape, and a brush unit is mounted on the other side surface in the axial direction of the base unit. In such a processing brush, the rotating shaft of the base unit is mounted to a drive source (rotation actuator) to rotate the entire processing brush, thereby allowing the brush unit to be pressed against a processed surface. This leads to a removal of an object to be removed (such as a flash) from the processed surface.